FRIDAY, Dec. 4 (HealthDay News) -- Monkeys can recognize photographs of other monkeys they know, proving that they can both detect differences in faces and figure out if they've seen them before, researchers report.
The study also shows that capuchin monkeys can decipher the two-dimensional nature of a photograph, the scientists authors noted.
The findings, reported by researchers at the Yerkes National Primate Research Center at Emory University in Atlanta, are published the week of Dec. 4 in the online early edition of the Proceedings of the National Academy of Sciences.
In the study, the monkeys looked at four photos, including one of a monkey they knew. They also looked at another four monkey photos, including one of a monkey they didn't know.
"This required monkeys to look at similar-looking faces and use their personal knowledge of group mates to solve the task," lead researcher Jennifer Pokorny, said in a university news release. "They readily performed the task and continued to do well when shown new pictures in color and in grayscale, as well as when presented with individuals they had never before seen in pictures, though with whom they were personally familiar."
According to the researchers, previously, there hasn't been evidence that nonhuman primates can look at two-dimensional images and understand they represent things and animals from real life.
Learn more about the capuchin monkey from the Rainforest Alliance.
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